Recent reports have indicated a dramatic rise in the incidence of Autism spectrum disorders (ASD), which has devastating medical and financial impact worldwide. Complex genetic associations and the lack translational models that replicate the spectrum of human symptoms have significantly impeded efforts for therapeutic development and intervention. In this proposal, we will capitalize on exciting new genetic targeting technologies as well as genome-wide association studies, which have pinpointed SHANK3 as a leading disease risk factor prompting a new era in ASD research. The development of shRNA and ZFN strategies to manipulate genetic structure holds great promise for the generation of novel rhesus models with haploinsufficency or complete knockout of disease risk factors. The aims of this proposal involve two targeted approaches for the exploratory stage in the path to develop an ASD transgenic model; 1) genetic knockdown of SHANK3 with shRNA and 2) knockdown or knockout of SHANK3 with ZFN. Additionally, neural progenitor cells (NPCs) will be derived from ESCs listed above for evaluation of SHANK3 on neuronal functions. Collectively, the results yielded from this proposal will provide a critical and early benchmark for SHANK3 modulation on developmental processes and resulting neurological activity. More generally, the aims of this grant could have very broad implications for human recessive genetic diseases in addition to ASD. Notably, our team has extensive expertise necessary for successful implementation of the goals outlined above and, most importantly, have already obtained preliminary data strongly suggestive of a successful outcome. With the support of this exploratory award, we are confident that the necessary groundwork can be established such that the milestone effort to create a future ASD translational model will be achieved. Although the goals of this grant are high-risk, we strongly believe that the recent advancements in scientific technology are timely for the launching of a new approach to modeling complex human diseases.